1. Field of the Invention
A gate valve structure.
2. Description of the Prior Art
In the past, various types of gate valve structures have been devised and used. However, the major portion of such prior art valves have the operational disadvantages that an excessive force is required to open and close the same, and to the extent that it is not uncommon for one of these valves to become stuck in a partially open position.
A primary object of the present invention is to provide a gate valve that will minimize the force required to open and close the same by eliminating substantial interaction between the fluid forces on the gate and the mechanical elements which convert torque into a gate traveling force, and by so doing permit an operator to completely open or close the valve of the present invention in an emergency.
Another object of the invention is to provide a gate valve that is of substantially simpler structure than previously available gate valves, and one that minimizes the machining operation required in the fabrication thereof.
A still further object of the invention is to provide a gate valve in which the main gate chamber thereof may be smaller in its maximum dimension than is possible with prior art valves, and one that may be smaller and lighter than such devices but yet serve the same functions.
Yet another object of the invention is to supply a gate valve in which the machining operations thereon may be more conveniently performed than on prior art valves due to easier accessability thereto, and one that reduces the extent and cost of seal face lapping.